U.S. patent application number 12/398503 was filed with the patent office on 2010-06-03 for gateway module, communication method, and computer program product thereof.
This patent application is currently assigned to INSTITUTE FOR INFORMATION INDUSTRY. Invention is credited to Hung-Yun HSIEH, Kun-Hung LEE, Chen-Yung LIAO, You-En LIN.
Application Number | 20100136972 12/398503 |
Document ID | / |
Family ID | 42223289 |
Filed Date | 2010-06-03 |
United States Patent
Application |
20100136972 |
Kind Code |
A1 |
HSIEH; Hung-Yun ; et
al. |
June 3, 2010 |
GATEWAY MODULE, COMMUNICATION METHOD, AND COMPUTER PROGRAM PRODUCT
THEREOF
Abstract
A gateway module, a communication method, and a computer program
product thereof are provided. The gateway module is adapted for use
in a network framework comprising a mobile station, a plurality of
interworking units, a first wireless network, and a second wireless
network. The mobile station is located within the signal coverage
of the first wireless network and the second wireless network, and
accepts network service provided by the first wireless network. The
gateway module receives a handover request signal of the first
wireless network, selects a handover interworking unit from the
interworking units according to the handover request signal, and
transmits the handover request signal to the second wireless
network. Thereby, the mobile station can handover to the second
wireless network to accept the network service provided by the
second wireless network.
Inventors: |
HSIEH; Hung-Yun; (Taipei,
TW) ; LIAO; Chen-Yung; (Pingtung City, TW) ;
LIN; You-En; (Tanzi Town, TW) ; LEE; Kun-Hung;
(Taipei, TW) |
Correspondence
Address: |
PATTERSON THUENTE CHRISTENSEN PEDERSEN, P.A.
4800 IDS CENTER, 80 SOUTH 8TH STREET
MINNEAPOLIS
MN
55402-2100
US
|
Assignee: |
INSTITUTE FOR INFORMATION
INDUSTRY
Taipei
TW
|
Family ID: |
42223289 |
Appl. No.: |
12/398503 |
Filed: |
March 5, 2009 |
Current U.S.
Class: |
455/436 |
Current CPC
Class: |
H04W 36/0066 20130101;
H04W 36/0005 20130101; H04W 36/14 20130101 |
Class at
Publication: |
455/436 |
International
Class: |
H04W 36/00 20090101
H04W036/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 1, 2008 |
TW |
097146588 |
Claims
1. A gateway module for use in a network framework, the network
framework comprising a mobile station (MS), a plurality of
interworking units, a first wireless network, and a second wireless
network, the first wireless network having a first signal coverage
and providing a first network service, the second wireless network
having a second signal coverage and providing a second network
service, the MS being located within the first signal coverage and
the second signal coverage, the interworking units being located
between the first wireless network and the second wireless network,
the MS being connected to the first network service beforehand, the
gateway module comprising: a reception module, being configured to
receive a handover request signal from the first wireless network;
a process module, being configured to select a handover
interworking unit from the interworking units according to the
handover request signal; and a transmission module, being
configured to transmit the handover request signal to the second
wireless network via the handover interworking unit so that the MS
may handover to the second wireless network to connect to the
second network service.
2. The gateway module of claim 1, wherein the handover request
signal comprises MS information and session information, the
process module selects the handover interworking unit from the
interworking units according to the MS information and the session
information.
3. The gateway module of claim 1, wherein the reception module
further receives a handover response signal, having base station
(BS) candidate information of the second wireless network, from the
second wireless network via the handover interworking unit after
the second wireless network receives the handover request signal,
the transmission module transmits the handover response signal to
the first wireless network so that the first wireless network
receives the BS candidate information of the second wireless
network.
4. The gateway module of claim 1, wherein the reception module is
further configured to receive a network resource allocation signal
from the first wireless network, the transmission module transmits
the network resource allocation signal to the second wireless
network via the handover interworking unit so that the second
wireless network allocates a network resource of the second
wireless network according to the network resource allocation
signal.
5. The gateway module of claim 4, wherein the reception module
further receives a network resource allocation response signal from
the second wireless network via the handover interworking unit
after the second wireless network receives the network resource
allocation signal, the transmission module transmits the network
resource allocation response signal to the first wireless network
so that the first wireless network confirms that the network
resource of the second wireless network is allocated.
6. A communication method for use in a gateway module, the gateway
module being adapted to a network framework, the network framework
comprising a MS, a plurality of interworking units, a first
wireless network, and a second wireless network, the first wireless
network having a first signal coverage and providing a first
network service, the second wireless network having a second signal
coverage and providing a second network service, the MS being
located within the first signal coverage and the second signal
coverage, the interworking units being located between the first
wireless network and the second wireless network, the MS being
connected to the first network service beforehand, the
communication method comprising the steps of: receiving a handover
request signal from the first wireless network; selecting a
handover interworking unit from the interworking units according to
the handover request signal; and transmitting the handover request
signal to the second wireless network via the handover interworking
unit so that the MS may handover to the second wireless network to
connect to the second network service.
7. The communication method of claim 6, wherein the handover
request signal comprises MS information and session information,
the step of selecting the handover interworking unit further
comprises the step of: selecting the handover interworking unit
from the interworking units according to the MS information and the
session information.
8. The communication method of claim 6, further comprising the
steps of: receiving a handover response signal, having BS candidate
information of the second wireless network, from the second
wireless network via the handover interworking unit after the
second wireless network receives the handover request signal; and
transmitting the handover response signal to the first wireless
network so that the first wireless network receives the BS
candidate information of the second wireless network.
9. The communication method of claim 6, further comprising the
steps of: receiving a network resource allocation signal from the
first wireless network; and transmitting the network resource
allocation signal to the second wireless network via the handover
interworking unit so that the second wireless network allocates a
network resource of the second wireless network according to the
network resource allocation signal.
10. The communication method of claim 9, further comprising the
steps of: receiving a network resource allocation response signal
from the second wireless network via the interworking unit after
the second wireless network receives the network resource
allocation signal; and transmitting the network resource allocation
response signal to the first wireless network so that the first
wireless network confirms that the network resource of the second
wireless network is allocated.
11. A computer program product, storing a program of a
communication method for use in a gateway module, the gateway
module being adapted to a network framework, the network framework
comprising a MS, a plurality of interworking units, a first
wireless network, and a second wireless network, the first wireless
network having a first signal coverage and providing a first
network service, the second wireless network having a second signal
coverage and providing a second network service, the MS being
located within the first signal coverage and the second signal
coverage, the interworking units being located between the first
wireless network and the second wireless network, the MS being
connected to the first network service beforehand, the program
being loaded into the gateway module by a computer and comprising:
a program instruction A for a reception module to receive a
handover request signal from the first wireless network; a program
instruction B for a process module to select a handover
interworking unit from the interworking units according to the
handover request signal; and a program instruction C for a
transmission module to transmit the handover request signal to the
second wireless network via the handover interworking unit so that
the MS may handover to the second wireless network to connect to
the second network service.
12. The computer program product of claim 11, wherein the handover
request signal comprises MS information and session information,
the program instruction B further comprises: a program instruction
B1 for the process module to select the handover interworking unit
from the interworking units according to the MS information and the
session information.
13. The computer program product of claim 11, wherein the program
further comprises: a program instruction D for the reception module
to receive a handover response signal, having BS candidate
information of the second wireless network, from the second
wireless network via the handover interworking unit after the
second wireless network receives the handover request signal; and a
program instruction E for the transmission module to transmit the
handover response signal to the first wireless network so that the
first wireless network receives the BS candidate information of the
second wireless network.
14. The computer program product of claim 11, wherein the program
further comprises: a program instruction D for the reception module
to receive a network resource allocation signal from the first
wireless network; and a program instruction E for the transmission
module to transmit the network resource allocation signal to the
second wireless network via the handover interworking unit so that
the second wireless network allocates a network resource of the
second wireless network according to the network resource
allocation signal.
15. The computer program product of claim 14, wherein the program
further comprises: a program instruction F for the reception module
to receive a network resource allocation response signal from the
second wireless network via the handover interworking unit after
the second wireless network receives the network resource
allocation signal.; and a program instruction G for the
transmission module to transmit the network resource allocation
response signal to the first wireless network so that the first
wireless network confirms that the network resource of the second
wireless network is allocated.
Description
[0001] This application claims priority to Taiwan Patent
Application No. 097146588 filed on Dec. 1, 2008.
CROSS-REFERENCES TO RELATED APPLICATIONS
[0002] Not applicable.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention provides a gateway module, a
communication method and a computer program product thereof. More
specifically, the present invention provides a gateway module, a
communication method and a computer program product thereof for
handover in a heterogeneous network.
[0005] 2. Descriptions of the Related Art
[0006] With continuous advancement in science and technology, ever
higher requirements are being imposed on communications. Nowadays,
more and more importance is being attached to convenience of
communications in addition to requirements on quality of
communications. Among various communication means, wireless
communications are advantageous in that they provide higher
mobility by obviating the need of physical communication network
wiring. Therefore, wireless-communication-enabled products such as
cell phones, notebook computers and the like are gaining more and
more popularity in recent years and have become the mainstream
products in the consumer electronics market.
[0007] A product with wireless-communication function is generally
portable with the user, and thus, it can be considered as a mobile
station (MS). Because of the portability thereof, the mobile
station often has to handover between two heterogeneous networks in
order to maintain a certain level of quality of service (QoS)
between, for example, a worldwide interoperability for microwave
access (WiMAX) network and a 3G network. To accomplish the handover
between heterogeneous networks smoothly, a single interworking unit
between two heterogeneous networks is typically used in the prior
art to provide a route for handover signal communication. Bandwidth
and reliability of the route provided by the single interworking
unit generally vary with level of the interworking unit.
[0008] However, conventional handover between heterogeneous
networks is accomplished by only a single interworking unit, the
route of which can only provide inflexible bandwidth and
reliability. In other words, the route of such a single
interworking unit cannot provide appropriate bandwidth and
reliability according to an operation currently executed by the
mobile station. For example, if the route of the single
interworking unit has properties of small bandwidth and high
reliability while the mobile station is transmitting a video stream
for the user thereof to watch, these properties of the route will
be inappropriate for the video transmission currently underway
because such a video transmission generally requires larger
bandwidth in order to avoid the delays of video frames.
Consequently, this will result in low efficiency of the mobile
station's handover between the heterogeneous networks.
[0009] Accordingly, a pressing need exists in the art to provide a
solution capable of selecting appropriate interworking unit(s)
according to the operation currently executed by a mobile station
during handover between two heterogeneous networks, so that the
handover of the mobile station can be accomplished smoothly and
efficiently.
SUMMARY OF THE INVENTION
[0010] One objective of the present invention is to provide a
gateway module, a communication method and a computer program
product thereof. The gateway module is adapted for use in a network
framework comprising a mobile station, a plurality of interworking
units, a first wireless network and a second wireless network. The
first wireless network has a first signal coverage and provides a
first network service. The second wireless network has a second
signal coverage and provides a second network service. The mobile
station is located within the first signal coverage and the second
signal coverage. The interworking units are located between the
first wireless network and the second wireless network. The mobile
station is connected to the first network service beforehand. After
receiving a handover request signal from the first wireless
network, the gateway module selects a handover interworking unit
from the interworking units according to the handover request
signal so that the mobile station may handover from the first
wireless network to the second wireless network via the handover
interworking unit. Thereby, the network service originally provided
by the first wireless network will now be provided by the second
wireless network instead.
[0011] To this end, the gateway module of the present invention
comprises a reception module, a process module and a transmission
module. The reception module is configured to receive the handover
request signal from the first wireless network. The process module
is configured to select the handover interworking unit from the
interworking units according to the handover request signal. The
transmission module is configured to transmit the handover request
signal to the second wireless network via the handover interworking
unit so that the MS may handover to the second wireless network to
connect to the second network service.
[0012] Also to this end, the communication method of the present
invention is adapted for use in the gateway module, and comprises
the steps of: receiving the handover request signal from the first
wireless network; selecting the handover interworking unit from the
interworking units according to the handover request signal; and
transmitting the handover request signal to the second wireless
network via the handover interworking unit so that the MS may
handover to the second wireless network to connect to the second
network service.
[0013] Further to this end, the computer program product of the
present invention stores a program of a communication method for
use in the gateway module. The program is loaded into the gateway
module by a computer and comprises: a program instruction A for a
reception module to receive the handover request signal from the
first wireless network; a program instruction B for a process
module to select the handover interworking unit from the
interworking units according to the handover request signal; and a
program instruction C for a transmission module to transmit the
handover request signal to the second wireless network via the
handover interworking unit so that the MS may handover to the
second wireless network to connect to the second network
service.
[0014] As described above, according to the handover request signal
from the first wireless network, the present invention selects the
handover interworking unit from the interworking units for use in
handover of the mobile station to the second wireless network.
Specifically, as the first wireless network is now providing the
first network service to the mobile station, the handover request
signal comprises the information corresponding to the first network
service. According to the information corresponding to the first
network service in the handover request signal, the present
invention selects the handover interworking unit so that the
bandwidth and reliability of the route provided by the handover
interworking unit satisfy the needs of the first network service
currently executed/received by the mobile station. Thereby, the
mobile station may handover to the second wireless network smoothly
and efficiently, and the shortcoming associated with using only a
single interworking unit for the mobile station's handover in the
prior art is overcome effectively.
[0015] The detailed technology and preferred embodiments
implemented for the subject invention are described in the
following paragraphs accompanying the appended drawings for people
skilled in this field to well appreciate the features of the
claimed invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a schematic view of a network framework of the
first embodiment of the present invention;
[0017] FIG. 2 is a schematic view illustrating arrangement of
interworking units in the first embodiment;
[0018] FIG. 3 is a schematic view of a gateway module of the first
embodiment; and
[0019] FIG. 4 is a flowchart of the second embodiment of the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0020] In the following description, the present invention will be
explained with reference to embodiments thereof. However, these
embodiments are not intended to limit the present invention to any
specific environment, applications or particular implementations
described in these embodiments. Therefore, description of these
embodiments is only for purpose of illustration rather than to
limit the present invention. It should be appreciated that, in the
following embodiments and the attached drawings, elements unrelated
to the present invention are omitted from illustration; and
dimensional relationships among individual elements in the attached
drawings are illustrated only for ease of understanding, but not to
limit the actual scale.
[0021] A first embodiment of the present invention is illustrated
in FIG. 1, which is a schematic view of a network framework 1. The
network framework 1 comprises a mobile station 11, a first wireless
network 13, a gateway module 15, a second wireless network 17, a
corresponding node 19 and a plurality of interworking units (not
shown). In this embodiment, the first wireless network 13 is a
network based on the 3G wireless network standards, and the second
wireless network 17 is a WiMAX wireless network based on the IEEE
802.16 standards. It should be noted that, rather than being
limited thereto, the first wireless network 13 and the second
wireless network 17 may also be the networks based on other network
standards in other embodiments.
[0022] Furthermore, as the first wireless network 13 is based on
the 3G wireless network standards, the first wireless network 13
comprises apparatuses that make it operable, such as a 3GPP AAA
server, an SGSN, a GGSN, a UTARN or the like. Likewise as the
second wireless network 17 is based on the WiMAX wireless network
standards, the second wireless network 17 comprises apparatuses
that make it operable, such as a base station, an ASN GW, a CSN, a
WiMAX AAA server or the like. How these apparatuses comprised in
the first wireless network 13 and the second wireless network 17
are connected and interact with each other is well known to those
of ordinary skill in the art, and thus will not be further
described herein. To make the following description more clearly,
relationships between the interworking units and the mobile station
11, the first wireless network 13, the second wireless network 17,
and the corresponding node 19 will be described first. Referring to
FIG. 2, a schematic view of arrangement of the interworking units
is shown therein. As can be seen in FIG. 2, the interworking units
(i.e., the interworking units 1a and 1b) are located between the
first wireless network 13 and the second wireless network 17 as a
communication intermediary therebetween. How the mobile station 11,
the first wireless network 13, the second wireless network 17 and
the corresponding node 19 interact with the interworking units 1a
and 1b will be detailed hereinafter.
[0023] The first wireless network 13 has a first signal coverage
and provides a first network service 190. The second wireless
network 17 has a second signal coverage and provides a second
network service 194. The mobile station 11 and the corresponding
node 19 are located within the first signal coverage of the first
wireless network 13 and the second signal coverage of the second
wireless network 17. The mobile station 11 is connected to the
first network service 190 of the first wireless network 13
beforehand, for example, to execute image/voice transmission or the
like with the corresponding node 19 via the first wireless network
13. Specifically, in this embodiment, the mobile station 11 may be
considered as a mobile phone, a notebook computer or any other
electronic product with a wireless Internet accessing capability,
and is now connected with the first wireless network 13 and
receives the first network service 190 therefrom to communicate
with the corresponding node 19. The corresponding node 19 may be
different apparatuses depending on the content of the first network
service 190; for example, if the first network service 190 is voice
transmission, the corresponding node 19 may be a cell phone
communicating with the mobile station 11, and if the first network
service 190 is image transmission, the corresponding node 19 may be
an image server.
[0024] To explain the functions of the gateway module 15 in the
network framework 1 in detail, please refer to FIG. 3 together,
which is a schematic view of the gateway module 15. The gateway
module 15 comprises a reception module 151, a process module 153
and a transmission module 155, the functions of which will be
described hereinafter.
[0025] Assume that the user of the mobile station 11 is gradually
moving away from the first signal coverage of the first wireless
network 13 and has now entered the second signal coverage of the
second wireless network 17. In other words, for the mobile station
11, signal strength received from the first wireless network 13 is
fading away while that from the second wireless network 17 is
becoming stronger gradually. Hence, to maintain a certain level of
QoS, the first wireless network 13 transmits a handover request
signal 130 to the mobile station 11 and the gateway module 15 to
inform that the mobile station 11 shall handover to the second
wireless network 17. After receiving the handover request signal
130, the mobile station 11 transmits a handover response signal 110
to the first wireless network 13 to inform the first wireless
network 13 that the mobile station 11 is prepared for the
handover.
[0026] On the other hand, after the reception module 151 of the
gateway module 15 received the handover request signal 130 from the
first wireless network 13, the process module 153 of the gateway
module 15 selects, according to the handover request signal 130, a
handover interworking unit from the interworking units for use as a
communication intermediary between the first wireless network 13
and the second wireless network 17. As described above, in this
embodiment, the network framework 1 comprises the interworking
units 1a and 1b, so the process module 153 of the gateway module 15
selects a handover interworking unit from the interworking units 1a
and 1b according to the handover request signal 130. Here, it is
assumed that the interworking unit 1a is selected by the gateway
module 15 as the handover interworking unit.
[0027] Particularly, in this embodiment, the handover request
signal 130 at least comprises mobile station information and
session information, and the process module 153 of the gateway
module 15 selects the interworking unit 1a from the interworking
units 1a and 1b as the handover interworking unit according to the
mobile station information and the session information. It should
be noted that, in other embodiments, rather than being limited
thereto, the network framework 1 may comprise another number of
interworking units.
[0028] Then, the transmission module 155 of the gateway module 15
transmits the handover request signal 130 to the second wireless
network 17 via the interworking unit 1a so that the second wireless
network 17 learns that the mobile station 11 will handover to the
second wireless network 17 to connect to the second network service
194. To allow the mobile station 11 to handover to the second
wireless network 17, the second wireless network 17, after
receiving the handover request signal 130, transmits a handover
response signal 170 having base station (BS) candidate information
of the second wireless network 17. Then the reception module 151 of
the gateway module 15 receives the handover response signal 170 via
the interworking unit la, and the transmission module 155 of the
gateway module 15 transmits the handover response signal 170 to the
first wireless network 13. After receiving the handover response
signal 170, the first wireless network 13 further transmits the
handover response signal 170 to the mobile station 13.
[0029] According to the base station candidate information of the
second wireless network 17 incorporated in the handover response
signal 170, the mobile station 13 performs a selection procedure
112 with the second wireless network 17 and, from the base station
candidate information, selects an appropriate base station for use
to communicate with the second wireless network 17. Once the
appropriate base station is selected, the mobile station 13
transmits a selection signal 114 to the first wireless network 13
which, according to the selection signal 114, generates and
transmits a network resource allocation signal 136 to the gateway
module 15. The reception module 151 of the gateway module 15
receives the network resource allocation signal 136 from the first
wireless network 13, and then the transmission module 155 of the
gateway module 15 transmits the network resource allocation signal
136 via the interworking unit 1a to the second wireless network 17
so that the second wireless network 17 can allocate a network
resource thereof according to the network resource allocation
signal 136. The network resource includes network bandwidth,
network IP and quality of service.
[0030] After having allocated the network resource according to the
network resource allocation signal 136, the second wireless network
17 transmits a network resource allocation response signal 172
comprising information relating to the network resource. Further,
the reception module 151 of the gateway module 15 receives the
network resource allocation response signal 172 from the second
wireless network 17 via the interworking unit la, and the
transmission module 155 of the gateway module 15 transmits the
network resource allocation response signal 172 to the first
wireless network 13 so that the first wireless network 13 confirms
that the network resource of the second wireless network 17 is
allocated.
[0031] On the other hand, as the second wireless network 17 has
allocated the network resource according to the network resource
allocation signal 136, the network resource allocation response
signal 172 may be transmitted directly to the mobile station 11
from the second wireless network 17 so that the mobile station 11
can be informed of the network resource allocation of the second
wireless network 17. In other words, the mobile station 11 is able
to receive signals from both the first wireless network 13 and the
second wireless network 17 to enhance reliability of the signals in
the handover process.
[0032] Additionally, the corresponding node 19 now is still unaware
that the mobile station 11 has initiated handover to the second
wireless network 17, so the first wireless network 13 transmits a
mobile IP update signal 132 to the corresponding node 19 to inform
the corresponding node 19 that it shall communicate with the mobile
station 11 via the second wireless network 17. After receiving the
mobile IP update signal 132, the corresponding node 19 transmits a
mobile IP confirmation signal 192 to the second wireless network 17
to confirm that the mobile station 11 has indeed completed handover
to the second wireless network 17. Thereafter, the mobile station
11 may begin to communicate with the corresponding node 19 via the
second network service 194.
[0033] After receiving the mobile IP confirmation signal 192 from
the corresponding node 19, the second wireless network 17 further
transmits a disable signal 174 to the first wireless network 13 via
the interworking unit la, so as to disable the first network
service 190 provided by the mobile station 11. After receiving the
disable signal 174, the first wireless network 13 transmits a
disable signal 134 to the mobile station 11 so that the mobile
station 11 disables the GPRS function thereof according to the
disable signal 134. Then, the mobile station 11 transmits a disable
confirmation signal 116 to the first wireless network 13 to inform
that the GPRS function of the mobile station 11 has been disabled
indeed.
[0034] A second embodiment of the present invention is illustrated
in FIG. 4, which is a communication method for use in the gateway
module described in the first embodiment. The gateway module is
adapted for use in a network framework comprising a mobile station,
a plurality of interworking units, a first wireless network, and a
second wireless network. The first wireless network has a first
signal coverage and provides a first network service. The second
wireless network has a second signal coverage and provides a second
network service. The mobile station is located within the first
signal coverage and the second signal coverage, the interworking
units are located between the first wireless network and the second
wireless network, and the mobile station is connected to the first
network service beforehand. Specifically, the communication method
described in the second embodiment may be executed by a computer
program product. When the computer program product is loaded into
the gateway module by a computer and a program embodied therein is
executed, the communication method described in the second
embodiment can be accomplished. The computer program product may be
stored in a tangible machine-readable medium, such as a read only
memory (ROM), a flash memory, a floppy disk, a hard disk, a compact
disk (CD), a mobile disk, a magnetic tape, a database accessible to
a network, or any other storage media with the same function and
well known to those skilled in the art.
[0035] The communication method described in the second embodiment
comprises the following steps. Initially, step S21 is executed to
receive a handover request signal from the first wireless network,
wherein the handover request signal comprises mobile station
information and session information. Step S22 is executed to select
a handover interworking unit from the interworking units according
to the mobile station information and the session information.
Then, step S23 is executed to transmit the handover request signal
to the second wireless network via the handover interworking unit
so that the mobile station may handover to the second wireless
network to connect to the second network service.
[0036] Next, step S24 is executed to receive a handover response
signal, which has base station candidate information of the second
wireless network, from the second wireless network via the handover
interworking unit after the second wireless network receives the
handover request signal. Afterwards, step S25 is executed to
transmit the handover response signal to the first wireless network
so that the first wireless network receives the base station
candidate information of the second wireless network. Then, step
S26 is executed to receive a network resource allocation signal
from the first wireless network, and step S27 is executed to
transmit the network resource allocation signal to the second
wireless network via the handover interworking unit so that the
second wireless network allocates network resource of the second
wireless network according to the network resource allocation
signal.
[0037] Subsequent to the steps described above, step S28 is
executed to receive a network resource allocation response signal
from the second wireless network via the handover interworking unit
after the second wireless network receives the network resource
allocation signal. Finally, step S29 is executed to transmit the
network resource allocation response signal to the first wireless
network so that the first wireless network confirms that the
network resource of the second wireless network is allocated.
[0038] In addition to the aforesaid steps, the second embodiment
can also execute all the operations and functions set forth in the
first embodiment. How the second embodiment executes these
operations and functions will be readily appreciated by those of
ordinary skill in the art based on the explanation of the first
embodiment, and thus will not be further described herein.
[0039] In summary, according to a handover request signal from the
first wireless network, the present invention selects a handover
interworking unit from a plurality of interworking units for use in
handover of the mobile station to the second wireless network.
Specifically, as the first wireless network is now providing a
first network service to the mobile station, the handover request
signal comprises the information relating to the first network
service. According to the information relating to the network
service in the handover request signal, the present invention
selects the handover interworking unit so that the bandwidth and
reliability of the route provided by the handover interworking unit
satisfy the needs of the first network service currently
executed/received by the mobile station. Thereby, the mobile
station may handover to the second wireless network smoothly and
efficiently, and the shortcoming associated with using only a
single interworking unit for the mobile station's handover in the
prior art is overcome effectively.
[0040] The above disclosure is related to the detailed technical
contents and inventive features thereof. People skilled in this
field may proceed with a variety of modifications and replacements
based on the disclosures and suggestions of the invention as
described without departing from the characteristics thereof.
Nevertheless, although such modifications and replacements are not
fully disclosed in the above descriptions, they have substantially
been covered in the following claims as appended.
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